An analysis of flight data by Channel 4 News shows the extent that international air traffic continued, while Brits were told to stay home.
International arrivals included more than 450 flights from China’s main airports.
Around the same number came to the UK from New York, which now has the highest number of confirmed cases of any state in the US.
Arrivals also included at least 250 planes from Milan, in northern Italy – one of the early coronavirus hotspots – with another 206 coming from Rome.
The data, provided to Channel 4 News by Flight Radar, charts every international arrival to the UK between March 24 and May 15. Crucially, this includes cargo and other non-passenger planes.
Last week, one of the government’s scientific advisers said that 95,000 people came to the UK by air between 1 April and 26 April. But so far there is no official figure that covers the whole of the UK’s lockdown period, which started in March.
However, it is likely that most passengers were residents or citizens returning home.
The new flight figures come a day after Heathrow Airport announced that thermal screening technology is being trialled in Terminal 2’s immigration hall, to detect elevated temperatures of passengers arriving in the UK.
Some scientists have questioned the effectiveness of travel bans – especially when the virus is already widespread across a country.
The UEA’s Professor in Medicine, Paul Hunter, has previously said: “Travel bans have a poor record on preventing the spread of epidemic diseases. At best travel bans only delay the spread of an epidemic by a short while.”